Kymab victorious before UK Supreme Court in Regeneron appeal

The UK Supreme Court today has sided with biopharmaceutical company  Kymab, allowing its appeal in a suit involving  Regeneron and patents covering transgenic mice.

In a 4-1  decision, the Supreme Court allowed Kymab’s appeal against a 2018 English Court of Appeal decision which had concluded that Regeneron’s two patents were valid and infringed.

The case, heard by the UK’s highest court in February this year, concerns European patents (UK) number 1,360,287 and its divisional EP (UK) number 2,264,163, both of which cover transgenic mice.

In 2018, the English Court of Appeal reversed a finding that the two patents were insufficient, holding that the specifications of the patents disclose the claimed inventions “clearly enough and completely enough for them to be performed by a person skilled in the art”.

The appeals court concluded that Regeneron’s patents contained enough information to enable a skilled reader to insert some of the human material into a mouse’s genes to create one type of hybrid mouse, but the patents didn’t explain how to create a hybrid structure incorporating the full human variable region genes into the mouse’s genome.

However, the Court of Appeal found there was no need for the patents to explain how to make the full range of mice because Regeneron’s idea was a “principle of general application” and the sufficiency requirement was satisfied.

Kymab appealed against the appeal court’s sufficiency findings, claiming that it had wrongly interpreted and applied the law of sufficiency.

Lord Kitchin and Lady Arden both recused themselves from the suit, as they were two of the three judges who handed down the Court of Appeal decision at issue.

Today, the Supreme Court allowed the appeal, with Lord Briggs delivering the majority opinion.

Briggs said that the Court of Appeal had been influenced by the fact that Regeneron’s invention is a principle of general application, as its contribution to the field was present not only in mice which could be made in 2001, but also in mice which could be made using later scientific developments.

“To limit the patentee strictly to a monopoly over the products which can immediately be made would be to deprive the patentee of any reward for the public benefit which will be derived from the use of that same invention in future types of product,” added Briggs, when discussing the lower court’s conclusion.

While the appeals court’s decision came from a “sophisticated and internally logical process of reasoning”, said Briggs, he then asked whether it was part of the law or a legitimate development of it.

Turning to UK and EU case law, the court noted that the authorities establish a number of principles in this area. Patentees must not make overly broad claims and, if they claim the right to make a range of products, sufficiency means they must disclose enough information to enable a skilled person to make “substantially” all the types which are claimed.

Applying these principles to the case, the Supreme Court found that Regeneron’s patents didn’t enable a skilled person to make mice containing more than a very small section of the human variable region.

“Thus the claim to a monopoly over the whole of that range went far beyond the contribution which the product made to the art at the priority date, precisely because mice at the more valuable end of the range could not be made, using the disclosure in the patents,” said Briggs.

He concluded that the Court of Appeal’s analysis cannot be regarded as a legitimate development of the law.

According to the court, the sufficiency requirement is part of the “bedrock of the law”, worked out over time both in the UK and by the European Patent Office.

“To water down that requirement would tilt the careful balance thereby established in favour of patentees and against the public in a way which is not warranted by the European Patent Convention, and which would exceed by a wide margin the scope for the development of the law by judicial decision-making in a particular Convention state,” said Briggs.

Simon Sturge, CEO of Kymab, said: “We are grateful that the court has recognised the shortcomings of the Regeneron patents and reinforced the established law that requires that an invention is adequately enabled across its scope.”

Regeneron said that the decision renders the two patents invalid and revoked in the UK only. Its rights concerning these patents in other European jurisdictions remain in full force and effect.

“The ‘287 patent validity was upheld at the Europe-wide level by the Technical Board of Appeal of the European Patent Office (EPO) in 2015, and the ‘163 patent validity was upheld by EPO Opposition Division in 2018. Proceedings before the EPO’s Technical Board of Appeal on the ‘163 patent are ongoing,” added Regeneron.

Check back on LSIPR for full reaction and analysis of the case.

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